Mail handling apparatus



Nov. 22, 1960 M. A. STOVALL 2,951,035

MAIL HANDLING APPARATUS Filed Sept. 11, 1957 3 Sheets-Sheet 1 INVENT OR M/L 7'0N A. J7'0VALL ATTORNEYS Nov. 22, 1960 M. A. STOVALL MAIL HANDLING APPARATUS 3 Sheets-Sheet 2 Filed Sept. 11, 1957 INVENTOR. M/LTON 14. J'TOVALL ATTOf/VEKT Nov. 22, 1960 M. A. STOVALL 2,961,085

MAIL HANDLING APPARATUS Filed Sept. 11, 1957 s Sheets-Sheet 3 INVENTOR. M/A 701v 4. 670M411 BY *Qula United States PateftitiQ MAIL HANDLING APPARATUS Milton A. Stovall, Silver Spring, Md., assignor to Emerson Radio 8: Phonograph Corporation, Jersey City, N..l., a corporation of'New York Filed Sept. 11, 1957, Ser. No. 683,284

18 Claims. (Cl. 198-30) The present invention relates to a system and apparatus for the automatic hand'ing of flat articles having a relatively low mass-to-area ratio, and particularly of letter mail.

In my current economy, the expeditious handling and processing of mail has become vital to the efficient conduct of business and communication. The volume of mail pieces has become so large as to encumber and literally swamp postal facilities at the larger metropolitan post oflices, hand'ing many millions of pieces of mail daily. The problems of conveying, cancelling, and sorting this great volume of varied shapes and sizes of mail pieces have heretofore not been efficiently solved, resulting in delays in delivery of mail and uneconomical utilization of space, equipment and manpower.

In solving this problem of mail handling, a first step is to provide a rapid flow of mail pieces, preferably in a stream of single units to permit subsequent individual operations on such pieces, such as cancelling, sorting, stacking and the like. In general, mail is collected at post oflices or from mail boxes in batches having random orientation, and are hence first available only in bulk. A preliminary problem, with which the present invention is concerned primarily, is to convert stationary bulk mail or batches of mail into a rapidly flowing stream. A further problem is to orient the pieces of the stream in a uniform manner for subsequent operations.

The present invention will be described as particularly applied to a system for separating, transporting, and feeding letter mail, although it will be readily appreciated that the present apparatus has a wider utility than in this specific application and can be used wherever a large volume of flat light articles is to be processed. Considering the problem in its broader aspects, the present invention is adapted to receive a helter-skelter mass of stationary or slow-moving letter mail at its input. For present purposes, such letter mail, for example, may be any relatively flat article of limited maximum dimensions, such as less than 12 inches long by 6 inches wide by /1 inch thick, which will include all normal letters, while excluding larger flat articles, such as magazines or very large envelopes, generally termed flats, as well as books, packages and the like. At its output, the present invention provides a rapid stream of such letter mail, transported at a high velocity providing an average flow of the order of 30,000 pieces per hour.

The present system provides apparatus by which a substantially motionless pile of random-oriented letter mail, of generally horizontal position, is converted into a stream flow of the proper average quantity or number of pieces per unit time, and with the pieces uniformly oriented, as by being in a vertical plane with the longest dimension horizontal. By way of example, such an apparatus may deliver letter mail at a rate varying between 4 and 12 pieces per second with an average of 8 /3 pieces per second (500 pieces per minute), with pile or slow-moving batches of mail pieces into a stream' .In particular it is an object of the present invention" to provide a system and apparatus for converting astatic of pieces flowing at a high average velocity to facilitate subsequent, processing of the individual pieces, as by automatic cancelling, sorting, facing and stacking. These and other objects and advantages of the present invention will be more fully apparent from considerae point in the output stream.-

tion of the following description of a preferred embodi-f merit taken in conjunction with the appended drawings, in which Fig. 1 is a side elevation view of the input assembly of the system of the present invention;

Fig. 2 is a top plan view of the assembly of Fig. 1;

Fig. 3 is a fragmentary side elevation view of a portion of the assembly of Figs. 1 and 2, showing a batch metering apparatus;

Fig. 4 is a top plan view of a modification of a portion of the assembly of Figs. 1 and 2;

Fig. 5 is a side elevation view of the apparatus of Fig. 4;

Fig. 6 is a fragmentary perspective view of.another portion of the assembly of Figs. 1 and 2, showing another batch metering apparatus;

Fig. 7 is an enlarged fragmentary side elevation view of the output end of the assembly of Figs. 1 and 2;

Figs. 1 and 2 are views of a preferred form of appara-. tus embodying the present invention. The input letter mail is placed either manually or by conveyor means on a slowly moving horizontal hopper belt 11 driven at constant speed by suitable motive means, not shown, coupled to a drive belt 12 rotating a drive roller 13 over which belt 11 passes. By way of illustration, hopper belt 11 may generally have a speed of /2 inch per second." It will be understood that the input mail is merely piled on belt 11, as by dumping the contents of mail bags thereon, or by feeding from a preceding conveyor, or from culling apparatus or the like, so that the mail there is of random orientation and in many irregular layers.

At the output end of hopper belt 11, its load is dropped on an inclined weighing tray 14 from which themail pieces slide onto an inclined conveyor belt 24. As seen in Fig. 3, tray 14 is pivotally mounted at 15 and has an arm 16 secured to it on which a counterweight 17 is adjustably mounted. Weight 17 causes the end 18 of arm 16 to rotate clockwise in the absence of a load on tray 14, so that end 18 maintains a microswitch 19 in closed position. This maintains hopper belt 11 in motion by any suitable means. For example, the motordriving hopper belt 11 may be running continuously, and coupled to belt 12 (Fig. 1) through an electrically energized clutch whose circuit is controlled by switch 19. When a sufiicient batch of mail is passed to tray 14 from belt 11, it will rotate tray 14 and its arm 16 counterclockwise, to disengage arm end 18 from switch 19 to stop the hopper belt 11 until the tray load has been removed. The mail holding down the tray is gradually conveyed away by conveyor belt 24, described below, so as to lighten the load on tray 14 until it is raised by weight 17 which also restarts hopper belt 11 to convey more pieces to tray 14.

It is generally undesirable for long gaps to occur in supplying mail to tray 14. For this reason, suitable sensing devices, such as photocells, may be placed at the output end of hopper belt 11 to sense when'no mail exists there. In response to this condition, such photocells may speed up belt 11 until mail arrives at the sensing point; Such speed-up means'and their controls are Patented Nov. ,22, 196p,

either conventional or are readily devised by known techniques, and need not be described in further detail here.

In this way, the first step in the flow of mail is accomplished, -converting the 'original rough --mass into batches which are-singly fed to thesubsequent apparatus. By way of illustration, weight 17 may be selected "and set to provide for batches of the order .of 25 pounds each.

In place of the hopper belt '11 and'tray 14, the "arrangement shown in Figs. 4 and 5 may be used where desired. In this instance, a hopper 21 having a smooth low-friction inclined surface '22 and side walls 23 is adapted tov receive the bulkletter mail which slides down the inclined surface 22 toward conveyoribelt 24.

'In either ,case, 'belt '24 is continuously driven by a suitable motive means, similar to that of belt 11, by way of a drive b,e1t.,26. .IBelt ,24 is preferably very wide compared to the size of the mail pieces, such as 36 to 48 inches wide,.s o ,as to geta lateral distribution of .mail pieces. By way of illustration, ,its speed :may be of the order of 14 inches per second. The belt .24 is formed of a high-friction material, or may have lateral .cleats .or other friction-increasing means provided, to cause the bottom letters to adhere thereto, while upper letters tend to slide back because of the relatively lower friction therebetween. To facilitate this'shearing action between letters,.b,.elt.24 is.made fairly steepnsuch as of the order of 45 degrees or more, and thereby accomplishes a rough distribution .of mail pieces from hopper belt 11 .or hopper .21, while simultaneously vproviding greater rolevation for the mail piecesfor later operations. .At theupperend of belt 24, and in the path of mail pieces falling over the forward edge of belt 24, is a Weighing tray 28. Tray 28 is pivoted at 27 (Fig. 6) and has a counterweight bar 30 secured thereto. Weight 30 normallyurgestray 28 upward. A predetermined weight of mail @will pivot .tray 28 .downward, and it will thenaetuate a .microswitch 25 connected in a conventional manner to stop belt 24, as by de-energizing itszmotor .or, preferably, by :de-energizing a solenoid-operated clutch asin theicaseof the drive forbelt 11. Illustratively,'tray 28'may be actuated by a batch of mail of the order of one pound in weight, andthereby serves ;to convert the larger batches from tray 14 to'smaller batches. If belt 24.is stopped, itwill :nolonger-take the load from prior weighingtray 14, which will then'load'up to its operating weight before stopping hopper belt 11.

v'l hese'smaller batches fromgtray 28 are dropped onto a further horizontal conveyor belt 29 (Fig. 7) continuously driven in any suitable :manner, as by a motor through a suitable transmission means. The belt 29 and its associated apparatus serve to convert the small batches of mail into=still smaller batches, approximating anirregular stream, which is then formed into stream flow. The speed of belt 29 may illustratively be of the order of 5 inches persecond, which is smaller than that of belt 24 to encourage an ample supply of pieces for subsequent operation, despite-irregularities in the-volume or feeding ofmail supplied to the input ofbelt '24 Mounted over the forward end of belt 29 isa drum 34 continuously rotated by suitable means, as by a further drive belt 33 from a suitable motor. Drum 34 has a plurality 'of flexible fingers 36 secured thereto, which successivelywipe letters from "belt 29 into a curved chute 37. Fingers 36 are formed of high-friction material, and tend to engage and move forward only the uppermost letter if several are piled up thereunder, since the coeificient of friction between a finger and a letter is much higher than that between two letters. The tips of the fingers 36 may be made especially flexible, and the remainder resilient, so that the tips will contact a larger area of letter for greater friction, while the resilient remainders tend .to exert greater pressure on the letters, also for better friction between tip and letter. Preferably only a few fingers 36 are placed in a lateral line across belt 29 (three and four being illustrated) to have at must only about that number of letters simultaneously ejected into chute 37. By way of example, drum 34 may rotate at a speed of the order of 35 revolutions per minute, to move fingers 36 much faster than belt 29 travels. This speed also determines the average rate of flow of mail pieces. Thus, the 14 fingers illustratively shown, rotating at 3-5 revolutions per minute, provide approximately 500 operations per minute-or 30,000 per hour, corresponding to that many letters per hour if drum 34 is continuously supplied and sends 'out a letter for each finger operation.

Suitable means are provided to stop conveyor belt 29 while fingers 36 engage letters thereon, thereby increasing the degree of separation of letters. One form of such means is shown most clearly in Fig. 7, and constitutes a plurality .of wire feelers 31 located approximately over the area contacted by fingers "36,.but between the various fingers. These feelers'31'form a type of thickness gauge, and'sense when too thick a pile of'letters is beneath the fingers 356, in which case one or more of the feelers 31 Willactuate its microswitch 32. The microswitches are, by way of example, in series with the control 'for the drive of belt 29, and upon actuation of any switch 32, belt 29 is stopped, to halt the flow of batches of mail'to the fingers 36 until those fingers have cleared the mail directly beneath them. 'In this way, jamming of letters beneath fingers 36 is avoided, and the batches ofletters arrivingat drum 34 .are separated into individual letters. It will .be understood that other suitable desired means for stopping belt29 may be used, such as photo-electric sensers etc.

Up-to this point, the mail pieces have been handled fiat, with their large surfaces resting on the belts 11,24 and 29, and with no attempt at orientation, in order to obtain a rough conversion from a random mass or pileon hopper belt 11 or in hopper 21 to a crude stream; still uneven inflow, and with possible overlappings. Chute 37, however, by suitable forming, turns the pieces by degrees to a vertical plane, between guides 38, below which is a horizontal conveyor belt 39 continuously rotated on rollers or drums such as 41 by suitable motive means. The mail pieces ejected by fingers 36 thereby fall on edge onto belt 39 and are conveyed byiton-edge; generally an orientation function is accomplished here, since pieces falling on their long sides are stable, and continue inthat condition, whereas pieces falling on their short edges are generally unstable, and the inertia effect produced by belt 39 abruptly engaging a lower short edge causes a turning movement about the center of gravity of the piece, which tumbles it to its more stable position with longer edge horizontal. As an added orienting means, a knockdown can be placed over guides 38, spaced above belt 39 by somewhat less than the maximum mail piece width (illustratively 6 inches) so as to knock over any letters projecting above this amount. v.Alternatively, stumbling rolls may be used ,for causing up-ended letters to turn to their long sides, or beaded chains, or the like, which will yield to the mail pieces to minimize possible jams, may be suspended in between guides 38, suitably spaced from belt 39, tom:- complish the same purpose. 'Illustratively, belt 39 may have a speed of the order of 35 inches per second, which stretches out and tends to separate the mail pieces considerably. V

The apparatus described has thus converted a random pile ofmail pieces, generally lying flat or horizontal, into a stream flowing horizontally with the mail pieces maintained vertically, and oriented with their long taxes horizontal. This stream has a high and generally uniform average rate of flow, illustrativelyof the order of 30,000 pieces per hour, and may be readily supplied to subsequent apparatus for utilization and further processing.

While specific forms of weighing devicehave 'beenfillusmemes tra ted above, it will be understood that other known form of such device may be used as desired.

Since many variations of the foregoing described appa ratus can be readily devised without departing from the spirit of the present invention, it is to be understood that this description is illustrative only, and is not to be construed in a limiting sense, the present invention being defined solely by the appended claims.

What is claimed is:

1. Mail-handling apparatus for converting bulk' letter mail into a high average flow of substantially separated and oriented mail pieces comprising a hopper conveyor belt operating at a first low speed and adapted to receive said bulk mail in random fashion, means including a weighing device at the end of said hopper belt adapted to receive mail from said belt and responsive to a predetermined first weight of mail for stopping said hopper belt upon occurrence of said first weight upon said weighing device, an inclined separating conveyor belt, said weighing device being adapted to discharge said first weight of mail upon said separating belt, whereby said bulk mail is separated into batches corresponding to said weight, said separating belt having high surface friction whereby said mail pieces tend to separate out by the slippage of upper pieces relative to pieces therebeneath, said separating belt operating at a substantially higher speed than that of said hopper belt, means comprising a further weighing device in the path of mail pieces discharging from said separating belt for stopping said separating belt in response to the discharge of a second substantially smaller predetermined weight of mail from said separating conveyor upon said second weighing device, a further horizontal conveyor belt, said second weighing device being adapted to discharge said second weight of mail upon said further belt, whereby each of said batches is converted into a plurality of smaller batches corresponding to said-second weight, said further belt having a lower speed than that of said inclined separating belt, a plurality of high-friction flexible fingers mounted pivotally about an axis parallel to and across said further belt, means for continuously rotating said fingers at a high rate of speed to brush the surface of said further belt and to brush off single mail pieces therefrom, a curve-d chute in the path of said brushed-oil mail pieces for rotating said mail pieces into a-vertical plane, a horizontal output conveyor beneath said chute for transporting said pieces on edge, and means responsive to the occurrence of a predetermined thickness of mail pieces in the zone of operation of said fingers for stopping said further conveyor belt until all mail pieces are removed from said zone.

2. Mail-handling apparatus for converting bulk letter mail into a high average flow of substantially separated and oriented mail pieces, comprising means for converting said bulk mail into batches of a first predetermined weight and for conveying said batches at a first speed, an inclined separating conveyor belt, said first means being adapted to discharge saidbatches upon said separating belt, said separating belt having high'surface friction whereby said mail pieces tend to separate out by the slippage of upper pieces relative to pieces therebeneath, means comprising a weighing device in the path of mail pieces discharging from said separating belt for stopping said separating belt in response to the discharge of a second substantially smaller predetermined weight of mail from said separating conveyor upon said weighing device, a further horizontal conveyor belt, said weighing device being adapted to discharge said second weight of mail upon said further belt, whereby each of said batches is converted into a plurality of smaller batches corresponding to said second weight, said further belt having a lower speed than that of said inclined separating belt, a plurality of high-friction flexible fingers mounted pivotally about an axis parallel to and across said further belt, means for continuously rotating said fingers at a-high rate of speed to brush the surface of said further belt and to brush ofif single mail pieces therefrom, a curved chute in the path of said brushed-off mail pieces for rotating said mail pieces into a vertical plane, a horizon tal output conveyor beneath said chute-for transporting said pieces on edge, and means responsive to the occurrence of a predetermined thickness of mail pieces in the zone of operation of said fingers for stopping said further conveyor belt until all mail pieces are removed from said zone;

3. Mail-handling apparatus for converting bulk letter mail into a high average fiow of substantially separated and-oriented mail pieces comprising an inclined separating conveyor belt adapted to have said bulk mail supplied thereto, said separating belt having high surface friction whereby said mail pieces tend to separate out by the slippage of upper pieces relative to pieces therebeneath, means comprising a weighing device in the path of mail pieces discharging from said separating belt for stopping said separating belt in response to the discharge of a predetermined weight of mail from said separating conveyor upon said weighing device, a further horizontal conveyor belt, said weighing device being adapted to dis-' charge said weight of mail upon said further belt, whereby said bulk mail is converted into a plurality of batches corresponding to said weight, said further belt having a lower speed than that of said inclined separating belt, a plurality of high-friction flexible fingers mounted pivotally about an axis parallel to and across said further belt, means for continuously rotating said fingers at a high rate of speed to brush the surface of said further belt and to brush off single mail pieces therefrom, means in the path of said brushed-01f mail pieces for rotating said mail pieces into a vertical plane, ahorizontal output conveyor beneath said last means for transporting said pieces on edge, and means responsive to the occurrence of a predetermined thickness of mail pieces in the zone of operation of said fingers for stopping said further conveyor belt until all mail pieces are removed from said zone.

4. Apparatus as in claim 3 wherein said bulk-mailsupplying means comprises a hopper chute.

5. Mail-handling apparatus for converting bulk letter mail into a high average fiow of substantially separated mail pieces, comprising an inclined separating conveyor? belt adapted to have said mail supplied thereto, said separating belt having high surface friction whereby said mail'pieces tend to separate out by the slippage of upper pieces relative to pieces therebeneath, said separating belt operating at a'substantially higher speed than that of said hopper belt, means comprising a weighing device in the path of mail pieces discharging from said separating belt for stopping said separating belt in response to the discharge of a predetermined weight of mail from said separating conveyor upon said weighing device, a further horizontal conveyor belt, said weighing device being adapted todischarge said weight of mail upon said further belt, whereby said mail is converted into a plurality 'of batches corresponding to'said' weight, said further belt having a lower speed than that of said inclined separating belt, a plurality of high-friction flexible fingers mounted pivotally about an axis parallel to and across said-further belt, means for continuously rotating said fingers at a high rate of speed to brush the surface of said further belt and to brush off single mail pieces therefrom, and means responsive to the occurrence of a predetermined thickness of mail pieces in the zone of operation of said fingers for stopping said further conveyor belt until said mail pieces are removed from said zone.

6.' Mail-handling apparatus for converting bulk le't ter mail into a high'average fiow of substantially separated and oriented mail pieces, comprising means for converting said bulk mail into batches of a first predetermined weight and for conveying said batches at a first speed, means for modifying each ofsaid first batches to form therefrom a plurality of smaller hatches, a .horizontal conveyor belt for conveying said smaller batches at higherspeed, aplurality of high-friction flexiblefingers mounted pivotally about an axis parallel to and across .said belt, -means for continuously rotating said fingers at a high rate of speed to brush the surface of said belt to brush off single mail pieces therefrom, a curved chute in the path of said brushed-elf mail pieces for rotating said mail pieces .intoa vertical plane, ahorizontal output conveyor beneath said chute for transport ing saidpieces on edge, and means responsive to the occurrence of a predetermined thickness of mail pieces in the zone'of operation of .saidfingers for stopping said further conveyor belt.

7. Mail-handling apparatus for converting bulk letter mail into a high average flow of substantially separated mail pieces, comprising means for converting said bulk mail into batches of a first predetermined weight and for conveying said batches at a first speed, means for modifying each of said first batches to form therefrom a plurality of smaller batches, a horizontal conveyor belt for conveying .said smaller batches at higher speed, a plurality of-high-friction flexible fingers mounted pivotally about an axis parallel to and across said further belt, means for continuously rotating said fingers at a high rate of speed to brush the surface of said further belt and to brush off single mail pieces therefrom, and .means responsive to the'occurrence of a predetermined thickness of mail pieces in the zone of operation of said fingers for stopping said further conveyor belt.

8. Mail-handling apparatus for converting bulk letter mail into. a high average flow of substantially separated and oriented mail pieces, comprising an inclined separating conveyor belt, means for supplying said bulk mail to said separating belt, said separating belt comprising means for distributing said bulk mail lengthwise thereof, a further horizontal conveyor belt, means for supplying said mail to said further belt, a plurality of high-friction flexible fingers mounted pivotally about an axis parallel to and across said further belt, means for continuously rotating said fingers at a high rate of speed to brush the surface of said further belt to brush off single mail pieces therefrom, a curved chute in the path of said brushed-01f mail pieces for rotating said mail pieces into a vertical plane, a horizontal output conveyor beneath said chute for transporting said pieces on edge, and means responsive to theoccurrence of a predetermined thickness of mail pieces in the zone of operation of said fingers for stopping said further conveyor belt. v9. Mail-handling apparatus for converting bulk letter mail into a high average flow of substantially separated mail pieces, comprising an inclined separating conveyor belt, means for supplying said bulk mail to said separating belt, said separating belt comprising means for distributing said bulk mail lengthwise thereof, a further horizontal conveyor belt, means for supplying said distributed mail thereto, a plurality of high-friction fingers mounted pivotally about an axis parallel to and across said further belt, means for continuously rotating said fingers at a high rate of speed to brush the surface of said further belt to brush off single mail pieces therefrom, and means responsive to the occurrence of a predetermined thickness of mail pieces in the zone of operation of said fingers for stopping said further conveyor belt.

10. Mail-handlingapparatus for converting bulk letter mail into a high average flow of substantially separated and oriented mail pieces, comprising a conveyor belt, means for conveying said bulk mail in separated batches to said conveyor belt, a plurality of high-friction flexible fingers mountedpivotally about an axis parallel to and across said belt, means for continuously rotating said fingers at ahigh rate of speed to 'brush the surface of said belt to brush olf single mail ,pieces therefrom, means in thepath of said brushedcfi mail .IPi Qe forrotating said mail piecesinto a vertical plane, ;a horizontal output conveyor beneathsaidlast means for transporting said pieces on edge, and .means responsive to the occurrence of a predetermined thickness of mail pieces in the zone of operation of said fingers .for stopping said further conveyor belt.

11. Mail-handling apparatus for converting bulk letter mail into a high average flow of substantially separated mail pieces, comprising a conveyor belt, means for conveying said ,bulk mail to said conveyor belt, a plurality of high-friction flexible fingers mounted pivotally about an axis parallel to and across said belt with said fingers adapted to brush the surface of said belt, means for continuously rotating said fingers at a high rate of speed to brush the surface of :said belt in the direction of movement of said belt to brush off single mail pieces therefrom, and means responsive to the occurrence of an ex- .eesssively thick batch of mail pieces in the zone of operation of said fingers for stopping said conveyor belt.

12. Maihhandling apparatus for producing a high average flow of substantially separated and oriented mail pieces comprising a conveyor belt adapted to have mail pieces supplied to it in irregular fashion, a plurality of high-friction fingers mounted pivotally about an ax's parallel to and across said belt and adapted to brush the surface of said belt, means for continuously rotating said fingers at a high rate ofspeed to brush the surface of said belt in the .direction of its movement to brush off single mail pieces therefrom, a curved chute in the path of said brushed-01f mail pieces for rotating said mail pieces into a vertical plane, a horizontal output conveyor beneath said chute for transporting said pieces on edge, and means responsive to the occurrence of an excessively thick batch of mail pieces in the zone of operation of said fingers for stopping said first-mentioned conveyor belt.

13. Mail-handling apparatus for producing a high average flow of substantially separated mail pieces, comprising a conveyor belt adapted to have mail pieces supplied to it in irregular fashion, a plurality of high-friction flexible fingers mounted pivotally about an axis parallel to and across said belt and adapted to brush the surface of said belt, means for continuously rotating said fingers at a high rate of speed to brush the surface of said belt in the direction of its movement to brush off single mail pieces therefrom, and means responsive to the .occurrence of an excesssively thick batch of mail pieces in the zone of operation of said fingers for stopping said conveyor belt.

14. Mail-handling apparatus for producing a high average fiow of substantially separated and oriented mail pieces comprising a conveyor belt adapted to have mail pieces supplied to it in irregular fashion, a plurality of high-friction flexible fingers'mounted pivotally about an axis parallel to and across said belt and adapted to brush the surface of said belt, means for continuously rotating said fingers at a high rate of speed to brush the surface :of said belt in its direction of movement to brush off single mail pieces therefrom, a curved chute in the path of said brushed-off mail p'eces for rotating said mail pieces into a vertical plane, and a horizontal output conveyor beneath said chute for transporting said pieces on edge.

15. Mail-handling apparatus for producing a flow of substantially separated mail pieces comprising a conveyor belt adapted to have mail pieces suppl'ed to it in irregular fashion, a plurality of high-friction flexible fingers mounted pivotally about an axis parallel to and across said belt and adapted to brush the surface of said belt, and means for continuously rotating said fingers at a high rate of speed to brush the surface of said belt in the direction of movement of said belt to brush off single mail pieces therefrom.

16. Mail-handling apparatus for converting bulk letter mail into a high average flow of substantially separated and oriented mail pieces, comprising means for converting said bulk :mail :imo batches of. a first predetermined weight and for conveying said batches at a first speed, means for modifying each of said first batches to form therefrom a plurality of smaller batches, a horizontal conveyor belt for conveying said smaller batches at higher speed, means operating at a predetermined zone of said belt for discharging single mail pieces from said belt, means responsive to occurrence of an excessively thick batch of mail pieces at said zone for stopping said belt, and means for orienting said single mail pieces in a vertical plane.

17. Mail-handling apparatus for converting bulk letter mail into a high average flow of substantially separated mail pieces, comprising means for converting said bulk mail into batches of a first predetermined weight and for conveying said batches at a first speed, means for modifying each of said first batches to form therefrom a plurality of smaller batches, a horizontal conveyor belt for conveying said smaller batches at higher speed, means operating at a predetermined zone of said belt for discharging single mail pieces from said belt, and means responsive to occurrence of an oversupply of mail pieces at said zone for stopping sa d belt.

18. Apparatus for converting a mass of fiat light articles into a high average flow of substantially separated articles, comprising an inclined separating conveyor belt, means for supplying said mass of articles to said separating belt, said separating belt comprising means for distributing said mass of flat articles lengthwise thereof, a further horizontal conveyor belt, means for supplying said distributed articles thereto, a plurality of high-friction fingers mounted pivotally about an axis parallel to and across said further belt, and means for continuously rotating said fingers at a high rate of speed to brush the surface of said further belt to brush off single articles therefrom.

References Cited in the file of this patent UNITED STATES PATENTS 514,794 Waldron Feb. 13, 1894 1,374,809 Biasotti Apr. 12, 1921 1,487,882 Parker Mar. 25, 1924 2,006,870 Neuman July 2, 1935 2,221,396 Evoy Nov. 12, 1940 2,367,278 Hewlett Jan. 16, 1945 2,578,314 Muench Dec. 11, 1951 2,786,565 Eckart Mar. 26, 1957 FOREIGN PATENTS 711,840 Great Britain July 14, 1954 

